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Table of n, a(n) for n=0..20.
Partial sums of A000228 = number of hexagonal polyominoes (or planar polyhexes) with n cells.
Sequence in context: A151408 A121956 A176638 * A000103 A101292 A181899
Adjacent sequences: A131464 A131465 A131466 * A131468 A131469 A131470
Tanya Khovanova, Jul 26 2007